Gonad sparing sterilization surgery for dogs in clinical practice.

Gonadectomy (ovariohysterectomy/ovariectomy and orchiectomy) has been the standard of surgical sterilization in dogs and cats. In many countries it has been performed at peri-pubertal or early post-pubertal age in clinical practice and at pre-pubertal age in shelters with merit and in others for breeders that wish to enforce and ensure breeding restrictions before sale. Early age gonadectomy (pre, peri, and early post-pubertal) is increasingly being questioned due to potential health detriments, particularly in large and giant breed dogs. In clinical practice, clients are increasingly becoming aware of alternative options to reproduction control and seek advice from their veterinarian who play a crucial role in guiding these decisions. Hysterectomy in female dogs and vasectomy in male dogs offer a permanent surgical sterilization option without disruption of the hormones and can be performed at traditional age (5-12 months in many countries) or early age (6-10 weeks) via surgical or laparoscopic means. It is very important that the entire uterus, including the uterine body must be removed, as otherwise pyometra remains a possibility. In queens, persistent oestrus occurs and pseudocyesis may occur. This, together with unwanted behaviours in both sexes, excludes gonad sparing procedures as routine option for owned cats. Sterility with preservation of hormones (hysterectomy, vasectomy, epididymectomy) has been suggested for feral cat populations. Hysterectomy and vasectomy in dogs can offer an effective solution for those who wish to reduce risk of early loss of hormones, eliminate the inconveniences of bloody vaginal discharge and the risk of unwanted pregnancy in effort to postpone gonadectomy at a much later age. Long term studies regarding outcome are needed, hence in clinical practice, hysterectomy is mostly advised as method of delaying gonadectomy.